* Add MTU configuration option for Warp/WireGuard in Xray
Add mtu parameter to the Warp/WireGuard configuration in Xray.
Setting a specific MTU can help prevent packet fragmentation issues when tunneling traffic through Warp/Cloudflare. A value of 1280 is chosen as a safe default, which ensures compatibility across different networks and avoids potential connectivity issues.
* Update warp-outbound-over-wg.md